Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760032AbZAQNd0 (ORCPT ); Sat, 17 Jan 2009 08:33:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750847AbZAQNdR (ORCPT ); Sat, 17 Jan 2009 08:33:17 -0500 Received: from mail.klingt.org ([86.59.21.178]:47229 "EHLO klingt.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750783AbZAQNdQ (ORCPT ); Sat, 17 Jan 2009 08:33:16 -0500 Subject: Re: 2.6.28-rc9: oprofile regression From: Tim Blechmann To: Thomas Gleixner Cc: Andi Kleen , oprofile-list@lists.sf.net, linux-kernel@vger.kernel.org, Robert Richter , venkatesh.pallipadi@intel.com In-Reply-To: References: <1229869416.6911.1.camel@thinkpad> <1229894585.6898.6.camel@thinkpad> <49544497.9020900@linux.intel.com> <1230894257.6072.10.camel@thinkpad> <1231957184.13033.70.camel@thinkpad> <1232010853.6541.4.camel@thinkpad> <1232067181.6134.74.camel@thinkpad> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-DZ++Q4jAMtHfbtXmxLvh" Date: Sat, 17 Jan 2009 14:32:49 +0100 Message-Id: <1232199169.7016.12.camel@thinkpad> Mime-Version: 1.0 X-Mailer: Evolution 2.24.2 X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-3.0 (klingt.org [127.0.0.1]); Sat, 17 Jan 2009 14:32:52 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1880 Lines: 60 --=-DZ++Q4jAMtHfbtXmxLvh Content-Type: text/plain Content-Transfer-Encoding: quoted-printable hm, it seems a bit more complicated than i originally thought. trying to reconstruct commit b99170288421c79f0c2efa8b33e26e65f4bb7fb8, i found, that resetting counter_width in ppro_setup_ctrs, causes the issue. reverting part of the patch, resolved the issue: --- a/arch/x86/oprofile/op_model_ppro.c +++ b/arch/x86/oprofile/op_model_ppro.c @@ -79,8 +79,8 @@ static void ppro_setup_ctrs(struct op_msrs const * const = msrs) if (cpu_has_arch_perfmon) { union cpuid10_eax eax; eax.full =3D cpuid_eax(0xa); - if (counter_width < eax.split.bit_width) - counter_width =3D eax.split.bit_width; +// if (counter_width < eax.split.bit_width) +// counter_width =3D eax.split.bit_width; } =20 /* clear all counters */ however, trying to apply this patch to 2.6.28, the behavior is the same as before (one NMI) ... so possibly, it is a combination of two bugs, with similar symptoms ...=20 hth, tim -- tim@klingt.org http://tim.klingt.org Your mind will answer most questions if you learn to relax and wait for the answer. William S. Burroughs --=-DZ++Q4jAMtHfbtXmxLvh Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAklx3f8ACgkQdL+4qsZfVsucIQCeI+ENwhH4//h5kX0xtDq+tB6/ O08AnRfVPc/PWPbKKlyMBnBKM2/Utsm/ =oSvq -----END PGP SIGNATURE----- --=-DZ++Q4jAMtHfbtXmxLvh-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/